<?php
/**
 * Created by PhpStorm.
 * User: gzy
 * Date: 2021/3/2
 * Time: 19:45
 */
$str1 = null;
$str2 = false;
echo $str1==$str2 ? '相等' : '不相等111111111';
$str3 ='';
$str4 = 0;
echo $str3==$str4 ? '相等' : '不相等';
$str5 = 0;
$str6 = '0';
echo $str5===$str6 ? '相等' : '不相等';